The present invention is broadly concerned with a flexible tie strap used for supporting pipes, ductwork, wiring or the like. More particularly, it is concerned with a flexible tie strap having an adjustable fastener with a release mechanism for securing the tie strap to itself or to another strap.
Flexible tie straps are commonly employed to rig and support ductwork for heating, ventilating and air conditioning (HVAC) systems. They are also used as cable ties to support electrical wiring and fiberoptic cables. Such tie strap devices are typically of ratchet and pawl construction with parallel entry of a free end of the strap through a buckle member to form a loop which is used to encircle and support a pipe, duct or cable. One side of the strap includes ratchet teeth and the buckle member is equipped with a pawl. The free end of the strap is inserted through the buckle member and the pawl rides over the teeth as the strap is pulled through the buckle. The shoulder of the ratchet tooth adjacent the pawl locks the strap against reverse movement. Flexible tie straps of this construction are extremely effective in providing adjustable support without causing damage to flexible ducts and wires which easily might be crimped, bent or otherwise damaged by other types of hanger devices.
Once installed, such tie straps can be removed easily by clipping or cutting the strap. However, for some applications it is desirable to loosen and readjust the strap or to remove it entirely for reuse at a different location. Various attempts have been made to equip tie strap fasteners with release mechanisms. Such release mechanisms are not well configured for ease of operation and require substantial finger strength. They also generally require well developed manual dexterity, since they are not easily grasped. Operation of such release mechanisms can be facilitated by using a tool. However, it is preferred that the pawl be released manually, without resorting to use of a tool. During use, a tie strap and associated buckle are typically snugged against the duct or wire to be supported. Use of a tool to pry the pawl to a release position involves a risk that the tool will slip and cause damage to the adjacent duct or wire. Moreover, because the cost of flexible tie straps is relatively low, clipping and discarding a tie is the favored procedure where the fastener cannot be released quickly and easily. Collectively, this practice represents a not insubstantial waste.
There is thus a need for a flexible tie strap with a manual release mechanism that can be easily gripped using one hand to release the strap so that it can be withdrawn from the fastener for adjustment or removal without the use of a tool.